Poly(A)-specific ribonuclease subunit PAN2 (PAN2)

Poly(A)-specific ribonuclease subunit PAN2 (PAN2) is the large, catalytic subunit of the PAN2–PAN3 deadenylation complex, a highly conserved enzyme complex responsible for trimming the 3′ poly(A) tails of cytoplasmic mRNA in eukaryotes[1][4][6]. PAN2 contains a C-terminal exoribonuclease domain that belongs to the DEDD family of exonucleases, functioning in magnesium-dependent hydrolysis to release AMP from poly(A) mRNA tails via a two-metal (typically Mg²⁺) catalytic mechanism[1]. While PAN2 itself displays relatively low RNA affinity and modest catalytic activity alone, its deadenylation efficiency and specificity for poly(A) tracts are strongly stimulated by its interaction with its non-catalytic partner PAN3[4][5][6]. The substrate recognition of PAN2 is unusual: it recognizes the structural conformation (an A-form helix) of poly(A) RNA via contacts with the phosphate-sugar backbone rather than specific nucleotide contacts[1][3]. PAN2 also features a WD40 domain at its N-terminus, mediating protein-protein interactions required for complex assembly with PAN3[1]. The PAN2–PAN3 complex is pivotal for the initial shortening of poly(A) tails, promoting mRNA decay and controlling gene expression at the post-transcriptional level in eukaryotic cells[4][5]. Currently, PAN2 is not known as a direct therapeutic target or as a biomarker in clinical applications. Disruption of deadenylation can impact mRNA stability and gene expression, potentially contributing to disease states involving aberrant RNA metabolism, but no direct roles in human pathology have clearly been defined[4]. If any more specific data (e.g., drugs, clinical biomarkers, or direct links to therapeutic targeting or disease mutation) become available in future research, these should be appended. As of current understanding, the major function of this protein remains strictly enzymatic in mRNA turnover, with no established roles as a drug target or disease biomarker.

Other names

PAN2-PAN3 deadenylation complex catalytic subunit PAN2KIAA0710USP52PAN deadenylation complex subunit 2hPAN2inactive ubiquitin carboxyl-terminal hydrolase 52PAB1P-dependent poly(A)-specific ribonucleasepoly(A)-nuclease deadenylation complex subunit 2PAN2 homologPABP1-dependent poly A-specific ribonuclease subunitubiquitin specific peptidase 52ubiquitin specific protease 52PAB1P-dependent poly(A)-nucleasePABP-dependent poly(A) nuclease 2